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American Red Cross, Rockville, Maryland
Blood transfusion is a critical component of modern health care in all parts of the world. Approximately 75 million units of whole blood are collected worldwide, although the amount of available blood varies widely, and 83% of the global population has access to only 40% of the blood supply. The safety of the blood supply is a matter of great concern, and the global expectation is that, at a minimum, every unit of blood should be tested for markers of infection with hepatitis B virus (HBV), hepatitis C virus (HCV), and HIV. Additionally, the World Health Organization and the International Federation of Red Cross and Red Crescent Societies mandate the collection of whole blood from unpaid volunteer donors only, both as a critical ethical requirement and to assure the safety of the blood supply. Neither of these sets of requirements is being met in full in the developing world, although progress is being made toward their complete fulfillment. In addition to the transfusion of whole blood, human plasma is used in the manufacture of derivatives, including albumin and clotting factors. In most countries, the needs for such medications cannot be fully satisfied by plasma recovered during the collection of whole blood, and there is a parallel system for the collection of plasma specifically designated for further processing. It is common to pay the donors of such plasma, even in developed countries. Plasma for further manufacture may be collected in 2 ways. The simplest is to collect a unit of anticoagulated whole blood in a plastic container, separate the cellular elements from the plasma by centrifugation, and express the supernatant plasma into a second container. The cells are then infused back into the donor. The other approach uses a continuous-flow device that automatically separates plasma and returns the cells to the donora process termed "plasmapheresis."
In addition to measures to ensure the safety of donated blood, it is expected that the safety of the donors will be ensured through the use of sterile equipment and aseptic practices and through the assessment of the health of the donor before phlebotomy. Indeed, this safety is so much taken for granted that prospective donors are routinely reassured that they cannot contract AIDS or other bloodborne diseases as a result of giving blood. However, in this issue of the Journal of Infectious Diseases, Qian et al. [1] report on an epidemiological study of individuals from rural Shanxi Province in China, an area in which there had been illegal commercial plasma-collection activities. Approximately 22% of a randomly selected group of 538 villagers had sold blood or plasma between 1973 and 1998. Blood was collected in official blood-collection centers, government hospitals, andin almost 24% of casesillegal plasma-collection centers. The HCV seroprevalence rate in former donors was 27.7%, in marked contrast to the seroprevalence rate of 2.6% in nondonors. In the donor group, those who had sold plasma had an almost 8-fold higher risk of HCV infection than did the whole-blood donors. Results of the multivariate analysis implied that the major association was with the illegal plasma-collection centers, rather than the government hospitals and official blood-collection centers.
These data may seem strange or even inexplicable to most Journal readers. As is pointed out above, donating blood or plasma is a safe process that, when performed properly, does not have any risk of transmission of infectious disease. However, this safety has not always been ensured in every collection center in China and, in very rare cases, in some other countries. Two practices have led to documented extensive epidemics of HIV and HCV infection in plasma donors in China. The most egregious and most widely publicized practice was pooling the red blood cells from multiple plasma donors before reinfusion. Somewhat more innocent is a practice that I saw many years ago in a plasma-collection center in Chengdu, in which the needles used for collection and reinfusion were recovered, supposedly sterilized, and reused. The sterilization was clearly ineffective, because the HCV seroprevalence rates in the donors were directly correlated with the frequency of donation.
Another observation in Qian et al.'s study is the significantly increased HCV seroprevalence rate in individuals who had received blood transfusions. The frequency of such transfusion-transmitted infections may well have been exacerbated by the increased HCV seroprevalence rate in the donor population. However, it is likely that many transfusions had been given before donated blood was routinely tested for HCV antibodies, because the test was not available before 1992 and was likely not immediately implemented in rural China. Indeed, in many parts of the developing world, when the testing of donated blood is incomplete, the test for antibodies to HCV is the one that is most likely to be omitted (see, for example, Schmunis and Cruz [2]).
There are lessons to be learned from these observations. First, however, it is important to note that an epidemiological study such as the one by Qian et al. is, of necessity, a snapshot of past events and should not be taken to define the present situation. Indeed, one reason that subjects stopped donating plasma was the (deliberate) closure of the illegal plasma-collection centers [1]. Although it is doubly unfortunate that these unacceptable blood- and plasma-collection techniques were in use during the emergence of the HIV epidemic in China, there seems to have been no attempt to conceal these events, as is indicated in a number of studies Qian et al. cite from the Chinese literature. In fact, the finding of HIV infection in donors led to a rapid promulgation of strict regulations to improve the safety of the entire blood-collection and blood-transfusion enterprise in China. In particular, national regulations now require that plasma be collected only by automated plasmapheresis, and all donations must be subjected to 2 different tests for HIV (in addition to the required tests for HBV and HCV). During a recent visit to China, I found that a significant concern about blood-collection safety was shared by officials, health professionals, and the educated public. Presently, in China, 9 million units of blood are collected annually; in contrast, in the United States, 14 million units are collected annually. However, most of the transfused blood in China is collected in well-run, modern facilities that are directly comparable with their peer institutions in the West. In other words, the silver lining of the epidemics caused by the unsafe practices at the illegal plasma-collection centers in China has been an extensive and effective investment in the blood-collection enterprise and its regulation.
Another issue is the impact that unrestricted commercialism has on the safety of human-derived blood products. Although well-managed, ethical enterprises can and do clearly achieve an environment in which the safety of both the product and the donors is ensured at the highest level, it is also clear that shortcuts, shoddy practices, the pursuit of the bottom line, and a lack of oversight can have devastating outcomes, not only for patients, but also for donors. We should also be reminded that bloodborne infections are readily transmitted through inappropriate injection practices, not only in the developing world [3], but also in Western settings, by use of multidose vials, as is illustrated by a recent study of a Canadian blood donor [4].
References
1. Qian H, Yang Z, Shi X, et al. Hepatitis C virus infection in former commercial plasma/blood donors in rural Shanxi Province, China: the China Integrated Programs for Research on AIDS. J Infect Dis 2005; 192:1694700 (in this issue). First citation in article
2. Schmunis GA, Cruz JR. Safety of the blood supply in Latin America. Clin Microbiol Rev 2005; 18:1229. First citation in article
3. Frank C, Mohamed MK, Strickland GT, et al. The role of parenteral antischistosomal therapy in the spread of hepatitis C virus in Egypt. Lancet 2000; 355:8879. First citation in article
4. Larke B, Hu YW, Krajden M, et al. Acute nosocomial HCV infection detected by NAT of a regular blood donor. Transfusion 2002; 42:75965. First citation in article